1. Field of the Invention
The present invention relates to a conveyor configured to convey a sheet and to an image forming apparatus with the conveyor.
2. Description of the Related Art
An image is formed on a surface of a sheet conveyed inside an image forming apparatus such as a copier, a printer, and a facsimile device. When the image forming apparatus forms the image on the sheet under improper conveyance, in which, for example, the sheet obliquely runs with respect to a base conveyor line, the image will be tilted in the sheet.
Some image forming apparatus automatically forms images on both sides of a sheet and then discharges the sheet to the outside after a user selects a two-side printing mode. The image forming apparatus with the two-side mode printing function typically comprises a system to switch back the sheet after the image is formed on either side of the sheet.
The switch-back system switching the conveyance direction of the sheet from one direction to the other direction after temporary stop is one of the most difficult techniques for conveying the sheet in the image forming apparatus. Accordingly, there are various improvements for a conveyance mechanism configured to switch back a sheet.
The complicated system for switching back the sheet causes various problems such as the oblique feed of the sheet after the switch back operation. There are several known approaches to an increase in printing efficiency (productivity) of the image forming apparatus with the switchback function by improving switchback conveyance for the sheet, but no approach addresses resolving the oblique feed of the sheet after the switchback operation.